Adam Van Arsdale, assistant professor of anthropology, is teaching Introduction to Human Evolution this fall to just over 19,000 students—enough students, the Globe pointed out, to fill TD Garden. Among the things he said he has to think about are whether “he should have shaved that morning, and what [students] will tweet.”

“It opens you up to a lot of complaining,” Van Arsdale told the Globe, recalling the support one student enjoyed after complaining on Facebook about the way Van Arsdale had phrased a question on natural selection. “Fifty people ‘liked’ that negative posting.”

Smitha Radhakrishnan, assistant professor of sociology, will be teaching Introduction to Global Sociology next fall. She was invited to film a promotional video for the class over the summer and shared concerns about camera angles and her baby bump. “Being on the Internet indefinitely as a pregnant person is very different from teaching in front of 25 students in a class you’ve known for the whole semester and have a relationship with,” Radhakrishnan said.

“It’s a bit scary,” Rogers said, imagining the judgment of fellow experts. “I feel that I’m taking big risks putting my interpretation of a very controversial figure out there for the entire world, and not just 25 Wellesley students.”

Despite the challenges online professors may face, there are also many benefits. “One of the most exciting parts is the fact that the classes do reach a broad audience,” Van Arsdale told us. “The students are enthusiastic and they're putting the time in to something for which they're not even getting credit.”

In a blog post earlier this year, Van Arsdale estimated that he has taught approximately 1,000 students in his seven-plus years of teaching. “In one semester [online],” he wrote “I might teach five times as many students as I will have the opportunity to teach in my entire career here at Wellesley College.” He continued, “It is a larger classroom to talk about issues of human diversity and evolution than I have ever had before... if even 1,000 students exit the course with an improved understanding of and greater interest in human evolution, I will consider it a massive success.”